 Just two hours ago, Allied Air Forces began an attack on military targets in Iraq and Kuwait. Just after midnight on January 17, 1991, President George H.W. Bush gave the orders for U.S. forces to lead an attack on Saddam Hussein's army, making the transition from Operation Desert Shield to Operation Desert Storm in the Gulf War. Operation Desert Shield began August 2, 1990 and concluded January 16, 1991. The purpose of the operation was for the U.S. to build up forces in the Persian Gulf and to provide time to build up the Saudi Arabian defenses. Operation Desert Storm, led by U.S. Army General Norwich Hortzkopf, kicked off with an extensive aerial bombing campaign on Hussein's armies in Iraq and Kuwait around 3 a.m. the same day it began. The following day, President Bush authorized the order to call up to a million National Guardsmen in reservists to active duty for up to two years. February 24, 1991, the first Marine Expeditionary Force and Coalition forces began a ground assault on Iraqi defenses in the final chapter of Operation Desert Storm. Along the Persian Gulf, the 1st and 2nd Marine Divisions, with their four main task forces stormed Iraqi defenses and convinced the defenders that it was the main effort of attack. Meanwhile, heavily armored Allied forces attacked the Iraqi defenses in Iraq from behind. At the same time, Marine units of the 4th and 5th Marine Expeditionary Brigades in the Persian Gulf stopped the Iraqi troops who were anticipating the aquatic attack. Within a hundred hours, U.S. and Allied forces defeated the Iraqi Army with few U.S. casualties. President Bush declared a ceasefire February 28, which ended Operation Desert Storm.